While it is relatively easy to create VMs using the Qubes Manager GUI, personally I prefer to use the command line.
This tutorial on how to create Qubes OS VMs on the command line is generally aimed at beginners that want to learn how to efficiently script the creation of new Qubes VMs. It explains the different types or classes of VMs, how the volumes work and how to use the command line tools qvm-create, qvm-clone, qvm-prefs, qubes-prefs, qvm-run and qvm-volume to manage the different VMs.